The invention relates to a process and devices to destroy animal pests, especially insects, for example ants, termites, roaches, wasps, house beetles, or the like, as well as rats, mice, moles, or the like.
An agent for destroying insects, such as ants, termites, roaches, wasps, house beetles, etc. is known from DE-A-37 12 487. It is nonpoisonous and is harmless to humans and domestic animals. The agent is intended to be eaten by insects, thus reaching the digestive tract. The agent carbon dioxide is evolved in the digestive tract, as a result of which the insects die. An admixed aromatic material is intended to attract certain insect species. The known agent mainly consists of yeast, baking powder, sodium, bicarbonate, or similar gas-evolving materials. A disadvantageous feature is that the known agent attracts other pests, for example mice or rats, which can eat the agent without injury. In addition, the agent is not free from residues, but instead lies strewn on the ground, if it is not completely eaten up.
EP-A-0 247 555 relates to the preparation of a disinfestation agent containing an inert fluid and phosphine, obtained by hydrolysis of a water-replacing metal phosphide, especially intended for the gassing of grain silos, in order to destroy pests such as insects, as well as rodents, present in stores of such plant-origin foods. The intention is that of keeping a certain phosphine concentration constant for a rather long time, allowing carbon dioxide in a concentration range of several percent by volume as synergist for the phosphine, whereby the killing of insects is accelerated in time, and a reduction in the phosphine concentration becomes possible. Solid or liquid carbon dioxide, ice water, or water and metal phosphide are reacted in a pressure vessel to prepare the disinfestation agent. When the reaction ends, the disinfestation agent is drawn off through a relief valve as a gaseous mixture of carbon dioxide and phosphine. The known disinfestation agent is toxic and dangerous to handle, because of the phosphine. The action of a certain quantity of phosphine is increased by the presence of carbon dioxide. The agent acts as a poison.
In addition, many other toxic agents are known, to be used at certain concentrations. All toxic agents have many drawbacks.